A common practice in producing hydrocarbons is to fracture the hydrocarbon bearing formation. Fracturing the hydrocarbon bearing formation increases the overall permeability of the formation and thereby increases hydrocarbon production from the zone fractured. Increasingly a single wellbore may intersect multiple hydrocarbon bearing formations. In these instances each hydrocarbon bearing zone may be isolated from any other and the fracturing operation proceeds sequentially through each zone.
In order to treat each zone sequentially a fracturing assembly is installed in the wellbore. The fracturing assembly typically includes of a tubular string extending generally to the surface, a wellbore isolation valve at the bottom of the string, various sliding sleeves placed at particular intervals along the string, open hole packers spaced along the string to isolate the wellbore into zones, and a top liner packer.
The fracturing assembly is typically run into the hole with the sliding sleeves closed and the wellbore isolation valve open. In order to open the sliding sleeves a setting ball, dart, or other type of plug is deployed into the string. For the purposes of the present disclosure a ball may be a ball, dart, or any other acceptable device to form a seal with a seat.